GB848202A - Improvements relating to supplying tyre ply material to tyre building machines - Google Patents

Abstract

848,202. Feeding webs. SHAW & CO. Ltd., F. March 18, 1957 [March 21, 1956], No. 8791/56. Class 100(1) An apparatus for supplying plies to tyre building machines from ply-let off spools mounted on a supply stand, is characterised by an eddy current coupling or variable speed motor, means for effecting a driving connection between the coupling or motor and either the ply let-off spool in operative position, or alternatively the corresponding liner take-up spool, and control means for the coupling or motor which can be adjusted to enable the ply to be drawn off at the correct tension and speed. As shown, a plurality of ply let-off spools, 1, la, and liner take-up spools 5, 5a, are connected by chains 3 so as to pass around wheels 4 into operative position where the ply is unwound for supply to a tyre building machine, not shown. The spools 1, la are driven in operative position by a sprocket 6 engaging a chain 7 passing around sprockets 8 and 9. The sprocket 9 is rotatably mounted on a shaft 10 carried by an arm pivoted about the axis of the sprocket 9, the shaft 10 being urged upwardly by a spring 13 to maintain the chain taut. The sprocket 8 is mounted on a shaft 15 driven by a belt 18 passing around pulleys 19, 20. The pulley 20 is mounted on the output shaft of a reduction gear 21 driven by a motor 22 through an eddy current coupling 23. An electromagnetic brake 24 stops the shaft driving the reduction gear when required. Current supplied to the coupling 23 is controlled by a variable transformer, not shown, adjusted so that the coupling 23 receives an excitation sufficient to overcome the inertia and frictional resistance of the ply spool. Thus, the spool 1 is driven at a peripheral speed corresponding with the linear speed at which tyre ply material is consumed by the tyre building machine. In a modification, the ply spool is driven through a chain, by a variable speed motor controlled by a rheostat and variable choke, the setting of the choke being controlled by the position of a roller engaging the periphery of the ply material on the spool 1 so as to control the speed of the motor in accordance with the spool diameter. The chain may be actuated towards the sprocket on the spool by an electromagnet or air cylinder.